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John McBarron Hodgson, MD

Dr. Hodgson is an internationally acclaimed cardiologist who, prior to founding Santé Cardiology, was the Chief of Academic Cardiology at St. Joseph Hospital and Medical Center in Phoenix. Previously a faculty member at the Medical College of Virginia and Case Medical School in Cleveland, he has devoted much of his career to training the next generation of physicians. He has served in many administrative positions and developed four Cardiology Departments. Dr. Hodgson is a Past President of the SCAI and a founding member of the SCCT. He has published over 200 peer reviewed articles, 8 books or book chapters, holds two patents and developed the TeachIVUS and TeachFFR online simulation training tools.

Angioplasty recently sat down with Dr. Hodgson to talk about intravascular technologies. This interview is posted in two parts:

  • Part One discusses intravascular ultrasound (IVUS) and how it can increase the accuracy of stent placement, and the role of IVUS in the era of DES 2.0;
  • Part Two discusses Fractional Flow Reserve (FFR) with some thoughts on training and recommendations for patients.



John McBarron Hodgson, MD
John McB. Hodgson, MD
Santé Cardiology
Phoenix, Arizona

Q: You mentioned FFR, or Fractional Flow Reserve, which measures any reduction in blood flow across a section of the coronary artery. Can you explain how it’s done?

FFR Measuring Device
FloWire® Doppler Guide Wire image, courtesy Volcano Corporation

Dr. Hodgson: FFR uses a guide wire with a pressure sensor at the tip. We do 80% of ours through the diagnostic catheters, so you don't even need a guiding catheter. It's actually very easy to do; it takes one to two minutes, tops. We have it set up on every case. We use, for the most part, intracoronary adenosine as our hyperemic stimulus, although in rare cases we need to use intravenous adenosine if there are multiple lesions or ostial lesions.

The accuracy of the pressure measurement is fantastic. We typically do three measures for a given lesion, with escalating doses of adenosine, so that we're sure that we get maximal hyperemia, and typically the values don't differ by more than a hundredth, The other nice thing is there's a very small gray zone which, for me, runs between about .75 and .81, and in that area we use clinical judgment and other things to decide what to do. But it's unusual that a patient ends up in that zone -- usually they're .9 or .6 so the answer's very easy.

Q: How does measuring the reduced blood flow affect the patient’s treatment?
Dr. Hodgson: You have to make a couple of decisions when you go into the lab, and the most important one is understanding when not to do something. You need to be sure, that if you're going to do an interventional procedure, whether it's surgery or stenting or balloons, bare metal stents, whatever, you need to be sure that the patient really needs it.

Not all lesions need a stent. And people argue “Well, I have to do something….” Well you are doing something. You've made a diagnosis, presumably you're going to put that person on anti-thrombotic agents, agents for their lipids, control their blood pressure, encourage them to stop smoking, exercise, etc. So, you are doing something, but it may not be a stent. It's extremely clear, from both the nuclear data as well as all the FFR data, that if you do not have ischemia from a lesion, then there is no benefit to revascularizing it.

Probably the strongest data here is the DEFER trial (Deferral Versus Performance of PTCA in Patients Without Documented Ischemia) where they took cases where, due to blockages seen on the angiogram, the operator intended to put a stent in. If the FFR was abnormal, or ischemic, below .75, they went ahead and stented all of those; the ones that were above .75, they randomized, to go ahead and implant stents in half and leave the other half medically treated. Now at 5 year follow-up, the ones who were left to be medically treated did better in every regard: fewer events, fewer revascularizations, less angina, etc.

I feel there's a concept out there among many operators, that every lesion needs a stent, that by plaque-sealing, we're going to keep it from causing a problem in the future. But the data just does not support that, if the lesion is not ischemic.

And I think the COURAGE trial, again, that plays into that. In my mind, there's just no justification in a stable patient to stent a non-ischemic lesion. We're not talking about acute M.I.s, we're not talking about acute non-Q.M.I.s. We're talking about the run of the mill patient who somehow gets a false positive nuclear stress test, or somehow gets on the cath table, and they start stenting lesions. And there's a lot of that that goes on, unfortunately. So, step number 1, make sure that the lesion's really ischemic. If there's any suspicion, I think that FFR should be done in the lab, to be sure that you're not stenting a lesion which doesn't need to be done.

But I do think it's a mistake to tell patients, “Well, we're not going to do anything”, or “You don't need anything done”. I think the proper approach is to say “Listen. You're very lucky at this point. This blockage is not causing any issues that we need to do anything invasive with, and we're going to treat it aggressively with medical therapy”. It just depends on how you present it to the patient. You can tell them that they're lucky, that they don't have to have a stent. It's a good thing.

Q: For those who want to learn, what are the training opportunities?

Dr. Hodgson: The bulk of the training opportunities come through courses and dinners and things that are set up by the manufacturers. I think we've kind of gone past the phase where we offer specific IVUS training as part of the big interventional meetings. There are certainly always IVUS sessions at ACC or SCAI or AHA -- TCT uses a lot of IVUS. But they don’t do it as part of every case.

We go to the hospital, give a grand rounds or lecture or dinner meeting or cath conference or something. The most effective ones in my mind are ones where we stay and work in the lab with people to help them get through the fear factor of doing it. Another issue that's critically important is training the techs and nurses to be facile at using it. I run 6-8 courses a year; we bring in 20 people. Now we're doing a lot more dinner meetings, going out to the sites, so we can get more people there.

    Dr. Hidgson lecturing about IVUS at TCT
Dr. Hodgson lecturing about IVUS during a session at the annual TCT meeting

The truth is we've been struggling for 13 years, ever since we started the program when Cordis was co-marketing with Endosonics, to find a method which gets these guys excited. IVUS for whatever reason, just never caught on as being something that we have to do. You know when Rotablator came on everybody wanted to be trained. And when DVI came out everybody wanted to be trained. When FoxHollow came out everyone wanted to try it. In the early days, and I mean early '90s, there was a lot of interest in IVUS and a lot of people wanted to know about it, but then their interest falls off when they don't feel that it makes a big difference to them, and it's an attitude issue at that point.

A lot of younger fellows who've trained at a place that uses a lot of IVUS come out and can't imagine doing without it. Other fellows come out of training and their mentors were less interested in IVUS, and they come out with no interest in it. So, it's difficult.

The three things that we learned in the mid '90s were they didn't believe it improved patient outcomes, and we did a host of trials in the late '90s to prove that that wasn't true. Second thing was they felt it was too hard to interpret, and we've spent a lot of time and energy improving the interpretation and automating the border detection and all that kind of stuff, making the systems easier to use. And the third thing is they said it was, it took too much time, it was too difficult to do mechanically. We've got integrated systems now, we've got very easy to use catheters, and that's just not true.

Q: What about the online program, Teach IVUS – which is co-sponsored by Volcano Therapeutics and Boston Scientific?


Dr. Hodgson: I'm biased since I wrote it. It's a useful tool, sure. The nice thing about Teach IVUS and the thing that we do in all of our Teach products (you know we have Teach CTA and Teach FFR, as well) is that we give immediate expert feedback. So we require you to draw or mark or point to or label or do something interactive with the images, then you get immediate visual feedback as to what the right answer was, where the drawing should have been, where the border really was. And then we ask questions, based on your measurements: “What would you do now?” So we do some sort of teaching.

It's not about clinical decision making in terms of cases; it's about “can you interpret these images properly?” And so I think people can do that, it's non-threatening, you can do it in your spare time, there's nobody pressuring you. I think if every tech were to work on that, and a lot of labs use it that way, then they'd be much more comfortable doing the border tracing and border correction stuff that they need to do during a live case.

Q: What are the implications for patients here? Is this something they should know about and ask for?
Dr. Hodgson: I think so. I think for the most part if you ask doctors, “If you're having a heart attack, do you want angioplasty or thrombolysis?”, they all say they want angioplasty. If you ask doctors, “you need a stent in your proximal LAD, do you want them to use IVUS or not”, they'll all say yes. So they all know the answer. The patients, the educated ones will ask about it. I think it's something that should be talked about. We do have it on the SCAI web site describes some of these other ancillary tools. We've toyed with a direct patient advertising campaign. But I'm not sure how to get the message out to patients, because it really has to be targeted to people who are likely to have procedures. This is not a drug they can take, or a new exercise regimen. FFR and IVUS are only applicable during a cath. So you have to find the people who are about to get a cath and somehow educate them.

Q: Angioplasty.Org currently gets 100,000 visits a month. We’d like to think we’re helping.
Dr. Hodgson: That's fantastic! You should certainly encourage the patients to discuss with their doctors two key things:

  1. is this blockage really causing a restriction of blood flow, or lack of blood flow to the heart, or however you want to phrase it, and if not, I would prefer to continue my medical therapy, and
  2. If this blockage needs to have an intervention, how are you going to ensure that the stent, or whatever the intervention is, is going to be done optimally? Are you going to use IVUS or FFR or some other method to be sure that you've done a good job mechanically?

And those are two questions that every patient ought to ask when they go in. Are you sure I need this and what's the data, what's the proof, and number two, are you sure you did a good job? How are you documenting your job? If you get a “well it looks okay to me”, that's not good enough.

For the latest news and information about imaging, visit Angioplasty.Org's Intravascular Ultrasound Center.

(Return to Part One)

This interview was conducted in February 2008 by Burt Cohen of Angioplasty.Org.